Ion sources are used commercially in equipment for implanting selected ions in materials such as semi-conductor wafers in the manufacture of electronics components. Proposals have also been made to use ion implantation for changing the physical properties of materials. For example, it has been found possible to improve properties such as corrosion and wear resistance and to change the frictional charcteristics of metals by ion implantation.
In a typical commercial ion implanter, an ion beam is extracted from the plasma and is refined (classified) and accelerated towards a target material into which ions are to be implanted. The ion source should preferably have a long life and be capable of producing a high, stable current output. A well defined and stable beam is also desirable.